Wartsila 31, Руководство по эксплуатации продукта

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6.1.2 Heavy Fuel Oil (HFO)
Residual fuel grades are referred to as HFO (Heavy Fuel Oil). The fuel specification HFO 2
covers the categories ISO-F-RMA 10 to RMK 700. Fuels fulfilling the specification HFO 1
permit longer overhaul intervals of specific engine components than HFO 2.
Table 6-2 HFO specifications
Test method ref. Limit HFO 2 Limit HFO 1 Unit Property
16...24 16...24 cSt Viscosity, before injection pumps 1)
ISO 3104 700 700 cSt Viscosity at 50°C, max.
ISO 3675 or 12185 991 / 1010 2) 991 / 1010 2) kg/m³ Density at 15°C, max.
ISO 8217, Annex F 870 850 CCAI, max.
3)
ISO 8754 or 14596 Statutory requirements % mass Sulphur, max.
4) 5)
ISO 2719 60 60 °C Flash point, min.
IP 570 2 2 mg/kg Hydrogen sulfide, max. 6)
ASTM D664 2.5 2.5 mg KOH/g Acid number, max.
ISO 10307-2 0.1 0.1 % mass Total sediment aged, max.
ISO 10370 20 15 % mass Carbon residue, micro method, max.
ASTM D 3279 14 8 % mass Asphaltenes, max. 1)
ISO 3016 30 30 °C Pour point (upper), max.
7)
ISO 3733 or ASTM
D6304-C
1)
0.5 0.5 % volume Water, max.
ISO 3733 or ASTM
D6304-C
1)
0.3 0.3 % volume Water before engine, max. 1)
ISO 6245 or LP1001 1) 0.15 0.05 % mass Ash, max.
ISO 14597 or IP 501
or IP 470
450 100 mg/kg Vanadium, max. 5)
IP 501 or IP 470 100 50 mg/kg Sodium, max. 5)
IP 501 or IP 470 30 30 mg/kg Sodium before engine, max. 1) 5)
ISO 10478 or IP 501
or IP 470
60 30 mg/kg Alu Silicon, max.
ISO 10478 or IP 501
or IP 470
15 15 mg/kg Alu Silicon before engine, max. 1)
IP 501 or IP 470 30 30 mg/kg Used lubricating oil, calcium, max. 8)
IP 501 or IP 470 15 15 mg/kg Used lubricating oil, zinc, max. 8)
IP 501 or IP 500 15 15 mg/kg Used lubricating oil, phosphorus, max. 8)
Remarks:
Additional properties specified by Wärtsilä, which are not included in the ISO specification. 1)
Max. 1010 kg/m³ at 15°C provided that the fuel treatment system can remove water and solids (sediment, sodium, aluminium,
silicon) before the engine to specified levels. 2)
Straight run residues show CCAI values in the 770 to 840 range and have very good ignition quality. Cracked residues delivered
as bunkers may range from 840 to - in exceptional cases - above 900. Most bunkers remain in the max. 850 to 870 range at
the moment. CCAI value cannot always be considered as an accurate tool to determine the ignition properties of the fuel,
especially concerning fuels originating from modern and more complex refinery process. 3)
The max. sulphur content must be defined in accordance with relevant statutory limitations.
4)
Sodium contributes to hot corrosion on the exhaust valves when combined with high sulphur and vanadium contents. Sodium
also strongly contributes to fouling of the exhaust gas turbine blading at high loads. The aggressiveness of the fuel depends
on its proportions of sodium and vanadium and also on the total amount of ash. Hot corrosion and deposit formation are,
however, also influenced by other ash constituents. It is therefore difficult to set strict limits based only on the sodium and
vanadium content of the fuel. Also a fuel with lower sodium and vanadium contents than specified above, can cause hot
corrosion on engine components.
5)
The implementation date for compliance with the limit shall be 1 July 2012. Until that, the specified value is given for guidance. 6)
It shall be ensured that the pour point is suitable for the equipment on board, especially if the ship operates in cold climates. 7)
Wärtsilä 31 Product Guide - a1 - 18 October 2016 6-3
6. Fuel Oil System Wärtsilä 31 Product Guide